when the regiment supported the 16th Brigade during the final stages of the Kokoda Track campaign, while other elements of the regiment took part in the Battle of Buna–Gona and the defence of Wau. During this time, the regiment expanded existing doctrine for the deployment of artillery by deploying guns into forward areas by air. The regiment returned to Australia for reorganisation in August 1943, and did not see action again until late in the war. It returned to New Guinea in January 1945 to support operations in the Aitape–Wewak campaign, supporting the defence of the airfield around Aitape, the advance on Wewak and operations around Mount Shiburangu. The regiment was in occupation of these areas when the war ended on 15 August 1945. The last of the regiment returned to Australia in January 1946 and was disbanded several weeks later as part of the post war demobilisation. Post World War II 1st Field Regiment was raised on 25 May 1949 at North Head, Sydney. At that time it was the only regular artillery regiment. On the eve of the Vietnam War the Regiment consisted of 101st Field Battery and 105th Field Battery (Independent), both equipped with 105 mm L5 Pack Howitzers, 102nd Light (4.2 inch Mortar) Battery and a Headquarters Battery. In April 1965 the decision was taken to deploy the 1st Battalion, Royal Australian Regiment (1RAR) to Vietnam. This resulted in an expansion of artillery regiments by the addition of a third field battery. 1st Field Regiment's order of battle for deployment to Vietnam was 101st Field Battery, 105th Field Battery, 161st Battery, Royal New Zealand Artillery and Headquarters Battery. 1 RAR deployed to Vietnam in May 1965 with fire support initially provided by 161 RNZA; however, in September 1965 the 105th Field Battery arrived to provide additional fire support. With the expansion of the Australian force to two Battalion Groups in June 1966, the remainder of the Regiment, less 101st Field Battery, deployed to Vietnam accompanied by 103rd Field Battery, under the command of Lieutenant Colonel Richmond Cubis. In addition, six 155 mm M109 self-propelled howitzers from A Battery, US 2/35th Artillery Battalion were permanently attached at Nui Dat. On 18 August 1966, the Regiment took part in the Battle of Long Tan in support of D Company, 6 RAR, firing 3,198 rounds from their L5s in three hours of battle with the artillery proving critical in